With the Mark 4HD, Leupold took the legendary performance of its predecessors and gave it a slimmer maintube that's been packed full of professional-grade features. It starts with the Professional-Grade Optical System, delivering unmatched light transmission that's designed to perform in the most challenging conditions. Its industry-leading glare reduction provides a clear image in harsh, direct light. A 3-turn M1C3 dial tops the elevation turret, providing 165 MOA of adjustment in 1/4 MOA increments, and the patented ZeroLock ensures the dial won't move when knocked around. With its first focal plane reticle, 4.5-18x magnification range, and side focus parallax adjustments, engaging at mid-range is just as easy as identifying threats from a distance. And like all Leupold Scopes, the Mark 4HD is 100% waterproof, fogproof, rugged-built, and backed by the Leupold Lifetime Guarantee. More on the PR1-MOA first focal plane reticle Created with input from elite shooters and hunters, the PR1-MOA provides multiple aiming points for extreme long-range shots. With 40 MOA of measurement in each direction and a useful MOA-based grid in 1 MOA increments, you have a wealth of ballistic information at your disposal. And because it's on the first focal plane, the indicator markings are useful at all magnifications. Professional-Grade Optical System offers unmatched light transmission First focal plane Illuminated PR1-MOA reticle Motion Sensor Technology (MST) extends battery life by automatically deactivating illuminated reticles after five minutes 100% waterproof, fogproof and shockproof 34mm tube M1C3 3-turn elevation dial provides 165 MOA of adjustment ZeroLock system eliminates accidental dial movement ZeroStop for easy return to zero 1/4 MOA adjustments for windage and elevation Integrated throw lever Made in USA Backed by the Leupold Lifetime Guarantee Order today!